Consumers have long struggled with how to spot treat substrates, such as fabrics or hard surfaces, with cleaning compositions, in particularly those containing potentially damaging cleaning components such as oxidants, including liquid bleach compositions. One method consumers use in order to clean small areas with liquid bleach is to dip a cotton-tipped swab into the bleach and then treat that area using the cotton-tipped swab to control where bleach is applied. This method is somewhat messy regarding ease in wetting a cotton-tipped swab using a large bottle of bleach and does not enable a consumer to precisely apply the bleach where desired. Other issues occur with this method. Excess bleach has the potential to drip from the cotton-tipped swab onto other surfaces, which may be damaged by contact with the cleaning composition. If used to treat fabric, current commercial fabric bleaches will spread and wick into the fabric indiscriminately, bleaching adjacent areas not intended, such as with fabrics having both white and colored areas, which cannot be washed using a laundry bleach to remove stains, even if those stains are confined to a potentially bleachable portion of the fabric. For hard surfaces, application is generally in areas that are hard to reach without a small applicator and yet require applying a cleaning composition directly onto the stained or soiled area. One example is stained grout located in a corner of a shower stall next to wallpaper or a painted surface, or a stained tile next to a metal faucet, where the adjacent surfaces may be damaged or discolored by the cleaning composition. Clearly what is needed is a means to selectively apply a cleaning composition, both accurately and precisely to a selected area to effect treatment, without concern that such treatment will spread or wick into unintended areas. Prior art in this field includes the following documents:
DE 195 36714 discloses a clothing spot cleaning stick and covers the basic design and use of a personal cleaning pen. WO 01/04260 discloses a felt tip pen-like applicator with a nib. The disadvantages and limited use of this device stems from the need to use bleaching fluids of relatively high viscosity, which have a tendency to clog, thereby affecting the user's ability to precisely control the delivery of the bleaching fluid. U.S. Pat. No. 6,386,781 B1 also discloses an applicator for packaging and applying a liquid product that requires an axially movable block of absorbent material that is saturated in the composition when the product is not in use.
WO 01/04259 discloses a stain removal pen that requires the fabric treatment composition to be left to evaporate. However, the disadvantage of this invention is that it also requires sufficient mechanical performance so as to induce a certain frictional stress upon the fabric. The frictional stress required in the invention has to be high enough as to ensure good mechanical stain removal and good delivery of the fabric treatment composition. As a consequence this invention cannot be used in situations that require accurate and precise application of the cleaning composition because the use of a mechanical step promotes the wicking or spreading of the composition.
WO 01/04261 discloses a stain removal pen and method of stain removal for garments worn on the body. However the invention requires heating the fabric treatment composition in the range of that provided by direct or indirect body heat to be effective.